Moanica D'kay is the main antagonist of Welcome to Monster High, the reboot movie of the Monster High franchise.
She lives in a cemetary with her family. She hate normies (humans) since she and other monsters have been forced to hide in the shadows for centuries. She has a group of zomboy minions. Unlike the other monsters, she doesn't see the equality between them and the normies, so she wants to destroy all of the normies and take everything. After she was defeated by the ghouls, she promised that she will take her revenge and someday put an end to Monster High.
In Monster High Electrified, some fan was thinking that Moanica will redeem herself during the second movie of the reboot, but unfortunately it was a misinformation she was never go to be repented yet, because when Clawdeen decide to open her beauty salon, during a humanology class Moanica learn that all normies were afraid of the dark, so, her and her zomboys decide again to create the chaos, she really don't want monsters and normies to live togheter, but again the ghouls find a way to stop with the help of an electric monster named Znap.
- Her name is a play on words, between the word "moan" and the name Monica.
- She shares her first name with Moanica Yelps from "Back and Deader Than Ever", Ghoulia Yelps's older sister.
- Her surname is also a pun, as the sound resembles the word "decay", the rotting process of a body or an object.
- Her name has not yet, if ever will be, requested for a trademark, unknown if Mattel will ever make it officially trademarked, let alone request it.